The invention pertains to a method for reloading in a container storage space for standard containers, with a stacker crane for the containers that services the container storage space and can be controlled by a DP (data processing) system for logistical management, which can travel between the storage location of each container and a loading platform of a container transport vehicle that can drive into the region of the container storage space, wherein the stacker crane has a means of picking up the container from the loading platform and/or setting it down onto the platform, such as can be oriented with respect to the latter.
Container storage yards are required for short-term interim storage of standard containers, in order to enable the transfer of containers from one means of transport to another. Means of container transport are generally large container ships, railroad cars, trucks, trailers, or also AGVs (automated guided vehicles). At a container harbor, container ships are unloaded and the unloaded containers are temporarily kept in the container yard until further transport is possible. Vice versa, the containers are assembled and kept temporarily in a container yard of a harbor in order to be loaded subsequently onto a container ship. The land transport occurs by truck, trailer, railroad car or AGV, and in the present application the land transport is furnished by special trucks.
The large number of containers handled at a container yard requires fast and accurate loading and unloading of the means of transportation. A stacker crane transports the container from the container yard to the transport vehicle and vice versa. The stacker crane can be an automatic container stacker crane (ACS), or also a gantry crane or a one-legged gantry crane. Thus far, the placement of the container onto a means of transport by the stacker crane has been manually controlled. The stacker crane consists of a bridge and a trolley which can travel on it, while the bridge can travel on rails. The placing of the container suspended from the crane onto a transport vehicle is manually controlled by an operator. For the loading, an operator present in the parking position drives the container by means of the stacker crane into the vicinity of the transport vehicle, and then by slow “approach” he positions the container exactly on the transport vehicle. The approach involves repeated left/right and forward/backward moving of the ACS, as well as the lowering of the container, controlled and monitored by the operator on site. Likewise, when unloading the transport vehicle, the stacker crane is slowly brought up to the container manually by an operator, so that the crane can pick it up.
The large number of containers handled within a container yard necessitates a smooth, error-free, speedy, economical and long-lasting work process. In addition, it is desirable to increase the throughput of containers, i.e., the number of containers handled per unit of time. This will reduce the parking time for containers inside the container yard, the layover time for container ships, and the stopping time for the land transport vehicles. At the same time, this implies a shortening of the length of transport for the containers.
From European patent application EP 1 043 262 A1 there is already known a method for handling of standard containers at a container yard. This container yard has a controllable stacker crane for the containers, which can travel between a storage position for the container and a transport vehicle with a loading platform for the container. The stacker crane is provided with a means of picking up the load in order to set the container down on the loading platform or pick it up from the platform, such as can be oriented with respect to the container and the loading platform. The stacker crane also has a horizontally moveable trolley with a lifting mechanism, from which is suspended the means of picking up the container. On this load suspension device is arranged a sensor in the form of a video camera system, so as to automatically place the load suspension device on the container or pick up the container from the loading platform. Furthermore, a second sensor also in the form of a video camera system is fastened to the load suspension device, in order to adjust the stacker crane. The reference point for this is a wall with optical elements, which is arranged in the region of the parking place of the transport vehicle.
Furthermore, there is also already known from the international patent application WO 01/81233 A1 a system for orienting a load suspension device for containers. The load suspension device, designed as a spreader, has a CCD camera in the region of its twist locks for fastening the spreader to the corner points of a container. Thanks to the video signal obtained from the camera, an operator can thus set this spreader down in true position on a container in relation to its support points. This system can also work automatically in conjunction with a DP system.